Portable power bank



FIG. 1 is a front view of a portable power bank, showing my new design,the rear view being a mirror image thereof;

FIG. 2 is a top view, the bottom view being a mirror image thereof;

FIG. 3 is a left view thereof; and,

FIG. 4 is a right view thereof.

CLAIM The ornamental design for a portable power bank, as shown anddescribed.